Medical marijuana continues to stir up controversy with regard to the issue of impaired driving.

While registered medical marijuana patients that get behind the wheel of a car can certainly expect the same treatment as anyone operating a motor vehicle under the influence of prescription painkillers, many advocates are concerned that because of the way marijuana metabolizes in the body, a significant number of medicated citizens could end up wrongfully incarcerated.

Even though Colorado and Washington have attempted to police stoned driving by implementing a concept similar to how blood-alcohol content is measured, where a numerical value is set on the amount of THC an individual is allowed to have in their system while operating a vehicle, there is still not a lot of faith that this method should be considered the gospel. In fact, the measure failed six times before the THC-limit of five nanograms per milliliter was approved earlier this year.

“We have this notion that since we have a magic number for alcohol, we are going to have a similar number for marijuana,” said NORML deputy director Paul Armentano. “The problem is that marijuana is not metabolized and absorbed by the body in the same way alcohol is.”

Many experts agree with Armentano, providing substantial evidence that marijuana should be, in fact, treated very differently than alcohol. A recent study published in the Medical Marijuana Review shows that drivers with a blood alcohol level of .12% are 30 times more likely to be involved in a serious accident than drivers testing positive for any amount of marijuana in their system.

In Canada, marijuana advocates argue that applying a definitive number as a means for testing a person’s THC content, like lawmakers have done in Colorado and Washington, is extremely tricky because there is a wealth of evidence that proves experienced tokers are not getting as stoned on the same amount of weed as the nug newbie.

“There’s quite a bit of difference with a first-time, non-experienced marijuana user and somebody who’s using it every day for medical purposes or otherwise, in terms of impairment and how it affects you,” said Dana Larsen of Sensible BC.

Larsen says that unfortunately, the issue is touchy and difficult to remedy because no one wants to come across as if they are promoting impaired driving. However, he contends that in the case of medical marijuana, patients may actually drive better when they are high because they are less likely to be distracted by the symptoms of their conditions.

The challenge of the impaired driving debate appears to lie in the ability to develop an accurate bloodstream analysis that can properly measure the level of THC in an individual’s body without unjustly incriminating them.

So far, not one method, including the current blood test, has proven to accurately determine the level of intoxication of a marijuana user.